Benefits of Living Over Deceased Donor Kidney Transplantation in Elderly Recipients. A Propensity Score Matched Analysis of a Large European Registry Cohort.

Although kidney transplantation from living donors (LD) offers better long-term results than from deceased donors (DD), elderly recipients are less likely to receive LD transplants than younger ones. We analyzed renal transplant outcomes from LD versus DD in elderly recipients with a propensity-matched score. This retrospective, observational study included the first single kidney transplants in recipients aged ≥65 years from two European registry cohorts (2013-2020, n = 4,257). Recipients of LD (n = 408), brain death donors (BDD, n = 3,072), and controlled cardiocirculatory death donors (cDCD, n = 777) were matched for donor and recipient age, sex, dialysis time and recipient diabetes. Major graft and patient outcomes were investigated. Unmatched analyses showed that LD recipients were more likely to be transplanted preemptively and had shorter dialysis times than any DD type. The propensity score matched Cox's regression analysis between LD and BDD (387-pairs) and LD and cDCD (259-pairs) revealing a higher hazard ratio for graft failure with BDD (2.19 [95% CI: 1.16-4.15], p = 0.016) and cDCD (3.38 [95% CI: 1.79-6.39], p < 0.001). One-year eGFR was higher in LD transplants than in BDD and cDCD recipients. In elderly recipients, LD transplantation offers superior graft survival and renal function compared to BDD or cDCD. This strategy should be further promoted to improve transplant outcomes.

Application of machine-learning models to predict the ganciclovir and valganciclovir exposure in children using a limited sampling strategy.

Intravenous ganciclovir and oral valganciclovir display significant variability in ganciclovir pharmacokinetics, particularly in children. Therapeutic drug monitoring currently relies on the area under the concentration-time (AUC). Machine-learning (ML) algorithms represent an interesting alternative to Maximum-a-Posteriori Bayesian-estimators for AUC estimation. The goal of our study was to develop and validate an ML-based limited sampling strategy (LSS) approach to determine ganciclovir AUC0-24 after administration of either intravenous ganciclovir or oral valganciclovir in children. Pharmacokinetic parameters from four published population pharmacokinetic models, in addition to the World Health Organization growth curve for children, were used in the mrgsolve R package to simulate 10,800 pharmacokinetic profiles of children. Different ML algorithms were trained to predict AUC0-24 based on different combinations of two or three samples. Performances were evaluated in a simulated test set and in an external data set of real patients. The best estimation performances in the test set were obtained with the Xgboost algorithm using a 2 and 6 hours post dose LSS for oral valganciclovir (relative mean prediction error [rMPE] = 0.4% and relative root mean square error [rRMSE] = 5.7%) and 0 and 2 hours post dose LSS for intravenous ganciclovir (rMPE = 0.9% and rRMSE = 12.4%). In the external data set, the performance based on these two sample LSS was acceptable: rMPE = 0.2% and rRMSE = 16.5% for valganciclovir and rMPE = -9.7% and rRMSE = 17.2% for intravenous ganciclovir. The Xgboost algorithm developed resulted in a clinically relevant individual estimation using only two blood samples. This will improve the implementation of AUC-targeted ganciclovir therapeutic drug monitoring in children.

Cellular immunity against cytomegalovirus and risk of infection after kidney transplantation.

Introduction: Cytomegalovirus (CMV) infection remains a challenge following kidney transplantation (KTx). Currently, CMV-IgG serostatus at transplantation is used to individualize CMV preventive strategies. We assessed the clinical utility of CMV-IGRA for predicting CMV infection following KTx. Methods: We performed a nationwide prospective cohort study from August 2016 until December 2022. Data from all adult KTx recipients in Norway, n=1,546 (R+; n=1,157, D+/R-; n=260, D-/R-; 129), were included with a total of 3,556 CMV-IGRA analyses (1,375 at KTx, 1,188 at eight weeks, 993 one-year after KTx) and 35,782 CMV DNAemia analyses. Results: In R+ recipients CMV-IGRA status, measured at any of the time-points, could not identify any differential risk of later CMV infection. D+/R- recipients remaining CMV-IGRA negative 1-year after transplantation (regardless of positive CMV DNAemia and/or CMV IgG status at that time) had increased risk of developing later CMV infection compared to D+/R- recipients who had become CMV-IGRA positive (14% vs. 2%, p=0.01). Conclusion: Knowledge of pre-transplant CMV-IGRA status did not provide additional information to CMV-IgG serostatus that could improve current post-transplant CMV treatment algorithms. However, D+/R- recipients with a persisting negative CMV-IGRA one-year after transplantation remained at increased risk of experiencing later CMV infection. Therefore we advocate post-transplant CMV-IGRA monitoring in these patients.

Gastric Bypass vs Diet and Cardiovascular Risk Factors: A Nonrandomized Controlled Trial.

Importance: Roux-en-Y gastric bypass (RYGB) is associated with reduced cardiovascular (CV) risk factors, morbidity, and mortality. Whether these effects are specifically induced by the surgical procedure or the weight loss is unclear. Objective: To compare 6-week changes in CV risk factors in patients with obesity undergoing matching caloric restriction and weight loss by RYGB or a very low-energy diet (VLED). Design, Setting, and Participants: This nonrandomized controlled study (Impact of Body Weight, Low Calorie Diet, and Gastric Bypass on Drug Bioavailability, Cardiovascular Risk Factors, and Metabolic Biomarkers [COCKTAIL]) was conducted at a tertiary care obesity center in Norway. Participants were individuals with severe obesity preparing for RYGB or a VLED. Recruitment began February 26, 2015; the first patient visit was on March 18, 2015, and the last patient visit (9-week follow-up) was on August 9, 2017. Data were analyzed from April 30, 2021, through June 29, 2023. Interventions: VLED alone for 6 weeks or VLED for 6 weeks after RYGB; both interventions were preceded by 3-week LED. Main Outcomes and Measures: Between-group comparisons of 6-week changes in CV risk factors. Results: Among 78 patients included in the analyses, the mean (SD) age was 47.5 (9.7) years; 51 (65%) were women, and 27 (35%) were men. Except for a slightly higher mean (SD) body mass index of 44.5 (6.2) in the RYGB group (n = 41) vs 41.9 (5.4) in the VLED group (n = 37), baseline demographic and clinical characteristics were similar between groups. Major atherogenic blood lipids (low-density lipoprotein cholesterol, non-high-density lipoprotein cholesterol, apolipoprotein B, lipoprotein[a]) were reduced after RYGB in comparison with VLED despite a similar fat mass loss. Mean between-group differences were -17.7 mg/dL (95% CI, -27.9 to -7.5), -17.4 mg/dL (95% CI, -29.8 to -5.0) mg/dL, -9.94 mg/dL (95% CI, -15.75 to -4.14), and geometric mean ratio was 0.55 U/L (95% CI, 0.42 to 0.72), respectively. Changes in glycemic control and blood pressure were similar between groups. Conclusions and Relevance: This study found that clinically meaningful reductions in major atherogenic blood lipids were demonstrated after RYGB, indicating that RYGB may reduce CV risk independent of weight loss. Trial Registration: ClinicalTrials.gov Identifier: NCT02386917.

Changes in the epidemiology of kidney replacement therapy across Europe in 2020-the first year of the COVID-19 pandemic: an ERA Registry study.

BACKGROUND: In 2020, the coronavirus disease 2019 (COVID-19) pandemic caused disruptions in kidney replacement therapy (KRT) services worldwide. The aim of this study was to assess the effect of the COVID-19 pandemic in 2020 on the incidence of KRT, kidney transplantation activity, mortality and prevalence of KRT across Europe. METHODS: Patients receiving KRT were included from 17 countries providing data to the European Renal Association Registry. The epidemiology of KRT in 2020 was compared with average data from the period 2017-2019. Changes occurring during the first and second waves of the pandemic were also explored. RESULTS: The incidence of KRT was 6.2% lower in 2020 compared with 2017-2019, with the lowest point (-22.7%) during the first wave in April. The decrease varied across countries, was smaller in males (-5.2%) than in females (-8.2%) and was moderate for peritoneal dialysis (-3.7%) and haemodialysis (-5.4%) but substantial for pre-emptive kidney transplantation (-23.6%). The kidney transplantation rate decreased by 22.5%, reaching a nadir of -80.1% during the first wave, and was greatest for living donor kidney transplants (-30.5%). While in most countries the kidney transplantation rate decreased, in the Nordic/Baltic countries and Greece there was no clear decrease. In dialysis patients, mortality increased by 11.4% and was highest in those 65-74 years of age (16.1%), in those with diabetes as the primary renal disease (15.1%) and in those on haemodialysis (12.4%). In transplant recipients, the mortality was 25.8% higher, but there were no subgroups that stood out. In contrast to the rising prevalence of KRT observed over the past decades across Europe, the prevalence at the end of 2020 (N = 317 787) resembled that of 2019 (N = 317 077). CONCLUSION: The COVID-19 pandemic has had a substantial impact on the incidence of KRT, kidney transplant activity, mortality of KRT and prevalence of KRT in Europe with variations across countries.

Acute effects of oral mesna administration on the full amino acid profile and 3-methylhistidine: secondary results from the CYLOB dose-finding study.

Plasma total cysteine (tCys) is strongly associated with fat mass in humans. Mesna lowers plasma tCys in a dose-dependent manner, but it is not known whether it interferes with metabolism of other amino acids or protein. In this Phase-1 study, we show that a single dose of mesna administered at 400, 800, 1200 or 1600 mg to 6-7 individuals per dose only slightly affects amino acid profiles, with increases in plasma valine across dose levels. There were no effects of mesna on 3-methylhistidine, a marker of protein breakdown.

Long-term Outcomes After Kidney Transplantation From DBD Donors Aged 70 y and Older.

Background: Transplantation of kidneys from elderly donations after brain death (DBD) donors has increased owing to organ shortages. We aimed to assess the impact on long-term kidney transplant outcomes from DBD donors aged 70 y and older compared with kidneys from younger donors. Methods: From 2007 to 2022, 2274 first single kidney transplantations from DBD donors were performed at our center. Data from 1417 kidney transplant recipients receiving a DBD organ were included and categorized into 3 groups according to donor age: 70 y and older (n = 444, median age 74 y), 60-69 y (n = 527, median age 64 y), and a reference group consisting of donors aged 45-54 y (n = 446, median age 50 y). Kaplan-Meier plots and multivariate Cox regression with correction for recipient, donor, and transplant characteristics were used to investigate patient and kidney graft survival outcomes. Results: The median patient follow-up time was 9.3 y (interquartile range, 5.3-13.1). The adjusted hazard ratios for patient death in recipients of kidneys from DBD donors aged 70 y and older compared with 60-69 y and 45-54 y were 1.12 (95% confidence interval [CI], 0.92-1.36; P = 0.26) and 1.62 (95% CI, 1.26-2.07; P < 0.001), respectively. Compared with recipients of donors aged 60-69 y and 45-54 y, the adjusted hazard ratios for kidney graft loss in recipients of donors aged 70 y and older were 1.23 (95% CI, 1.02-1.48; P = 0.029) and 1.94 (95% CI, 1.54-2.45; P < 0.001), respectively. Conclusions: Transplantation of kidneys from DBD donors aged 70 y and older resulted in acceptable long-term outcomes and is encouraging.

Oral Drug Dosing After Gastric Bypass and Diet-Induced Weight Loss: Simpler Than We Think? Lessons Learned From the COCKTAIL Study.

This article summarizes the lessons learned from the COCKTAIL study: an open, three-armed, single-center study including patients with obesity scheduled for treatment with Roux-en-Y gastric bypass (RYGB) or nonsurgical calorie restriction, and a normal- to overweight control group. The clinical implications of the results from multiple peer-reviewed articles describing the effects of RYGB, severe caloric restriction, weight loss, and type 2 diabetes on the in vivo activity and protein expression of drug-metabolizing enzymes (cytochrome P450 (CYP) 1A2, 2C9, 2C19, and 3A) and transporters (DMETs; organic anion-transporting polypeptide (OATP) 1B1 and P-glycoprotein (P-gp)) are discussed in the perspective of three clinically relevant questions: (1) How should clinicians get the dose right in patients after RYGB? (2) Will drug disposition in patients with obesity be normalized after successful weight loss? (3) Are dose adjustments needed according to obesity and diabetes status? Overall, RYGB seems to have a lower impact on drug disposition than previously assumed, but clinicians should pay close attention to drugs with a narrow therapeutic range or where a high maximum drug concentration may be problematic. Whether obesity-related alterations of DMETs normalize with substantial weight loss depends on the DMET in question. Obesity and diabetes downregulate the in vivo activity of CYP2C19 and CYP3A (only obesity) but whether substrate drugs should be dose adjusted is also dependent on other factors that influence clearance, that is, liver blood flow and protein binding. Finally, we recommend frequent and individualized follow-up due to high inter- and intraindividual variability in these patients, particularly following RYGB.

The ERA Registry Annual Report 2021: a summary.

Background: The European Renal Association (ERA) Registry collects data on kidney replacement therapy (KRT) in patients with end-stage kidney disease (ESKD). This paper is a summary of the ERA Registry Annual Report 2021, including a comparison across treatment modalities. Methods: Data was collected from 54 national and regional registries from 36 countries, of which 35 registries from 18 countries contributed individual patient data and 19 registries from 19 countries contributed aggregated data. Using this data, incidence and prevalence of KRT, kidney transplantation rates, survival probabilities and expected remaining lifetimes were calculated. Result: In 2021, 533.2 million people in the general population were covered by the ERA Registry. The incidence of KRT was 145 per million population (pmp). In incident patients, 55% were 65 years or older, 64% were male, and the most common primary renal disease (PRD) was diabetes (22%). The prevalence of KRT was 1040 pmp. In prevalent patients, 47% were 65 years or older, 62% were male, and the most common PRDs were diabetes and glomerulonephritis/sclerosis (both 16%). On 31 December 2021, 56% of patients received haemodialysis, 5% received peritoneal dialysis, and 39% were living with a functioning graft. The kidney transplantation rate in 2021 was 37 pmp, a majority coming from deceased donors (66%). For patients initiating KRT between 2012-2016, 5-year survival probability was 52%. Compared to the general population, life expectancy was 65% and 68% shorter for males and females receiving dialysis, and 40% and 43% shorter for males and females living with a functioning graft.

Very Low Frequency of Pathological Findings in One-year Protocol Biopsies of Uneventful Standard Risk Kidney Transplant Recipients: Results From the Nordic Protocol Biopsy Study.

Background: The clinical significance of kidney transplant protocol biopsies has been debated. We studied the frequency of borderline changes and T cell-mediated rejection (TCMR) in 1-y protocol biopsies in standard risk kidney transplant recipients. Methods: Consecutive non-HLA-sensitized recipients of kidney transplants between 2006 and 2017, who underwent a protocol biopsy at 1 y in 2 national transplant centers were studied retrospectively (N = 1546). Donor-specific HLA antibodies (DSAs), graft function (plasma creatinine), and proteinuria were measured at the time of 1-y protocol biopsy. The occurrence of subclinical acute TCMR (i2t2v0 or higher) or borderline changes suspicious of TCMR (i1t1v0 or higher) in the protocol biopsy was studied, together with frequency of findings causing changes in the composite score iBox. Results: Subclinical acute TCMR was detected in 30 of 1546 (1.9%) of the protocol biopsies, and borderline or TCMR in 179 of 1546 (12%). Among patients with no history of acute rejection, and no proteinuria or DSA, TCMR was detected in only 1 of 974 (0.1%) and borderline or TCMR in only 48 of 974 (4.9%) patients at 1 y. In the absence of proteinuria (<30 mg/g, or equivalent as measured with a negative dipstick proteinuria) or DSA, or history of acute rejection, only 50 of 974 (5.1%) biopsies showed any lesions significant for the iBox score. Conclusions: The likelihood of pathological findings in 1-y protocol biopsies in non-HLA-sensitized patients without previous immunological events is low. Clinical usefulness of protocol biopsies seems limited in these patients.

Long-term Kidney Transplant Survival Across the Globe.

BACKGROUND: The outcomes after kidney transplantation (KT), including access, wait time, and other issues around the globe, have been studied. However, issues do vary from one country to another. METHODS: We obtained data from several countries from North America, South America, Europe, Asia, and Australia, including the number of patients awaiting KT from 2015, transplant rate per million population (pmp), proportion of living donor and deceased donor (LD/DD) KT, and posttransplant survival. We also sought opinions on key difficulties faced by each of these countries with respect to KT and long-term survival. RESULTS: Variation in access to KT across the globe was noted. Countries with the highest rates of KT pmp included the United States (79%) and Spain (71%). A higher proportion of LD transplants was noted in Japan (93%), India (85%), Singapore (63%), and South Korea (63%). A higher proportion of DD KTs was noted in Spain (90%), Brazil (90%), France (85%), Italy (85%), Finland (85%), Australia-New Zealand (80%), and the United States (77%). The 5-y graft survival for LD was highest in South Korea (95%), Singapore (94%), Italy (93%), Finland (93%), and Japan (93%), whereas for DD, it was South Korea (93%), Italy (88%), Japan (86%), and Singapore (86%). The common issues surrounding KTs are access and a limited number of LDs and DDs. Key issues identified for long-term survival were increasing age of donors and recipients, higher recipient comorbidity, and posttransplant events, such as alloimmune injury to the kidney, infection, cancer, and suboptimal adherence to therapy. CONCLUSIONS: A unified approach is necessary to improve issues surrounding KT as the demand continues to increase.

Optimization of Ganciclovir and Valganciclovir Starting Dose in Children by Machine Learning.

BACKGROUND AND OBJECTIVES: Ganciclovir (GCV) and valganciclovir (VGCV) show large interindividual pharmacokinetic variability, particularly in children. The objectives of this study were (1) to develop machine learning (ML) algorithms trained on simulated pharmacokinetics profiles obtained by Monte Carlo simulations to estimate the best ganciclovir or valganciclovir starting dose in children and (2) to compare its performances on real-world profiles to previously published equation derived from literature population pharmacokinetic (POPPK) models achieving about 20% of profiles within the target. MATERIALS AND METHODS: The pharmacokinetic parameters of four literature POPPK models in addition to the World Health Organization (WHO) growth curve for children were used in the mrgsolve R package to simulate 10,800 pharmacokinetic profiles. ML algorithms were developed and benchmarked to predict the probability to reach the steady-state, area-under-the-curve target (AUC0-24 within 40-60 mg × h/L) based on demographic characteristics only. The best ML algorithm was then used to calculate the starting dose maximizing the target attainment. Performances were evaluated for ML and literature formula in a test set and in an external set of 32 and 31 actual patients (GCV and VGCV, respectively). RESULTS: A combination of Xgboost, neural network, and random forest algorithms yielded the best performances and highest target attainment in the test set (36.8% for GCV and 35.3% for the VGCV). In actual patients, the best GCV ML starting dose yielded the highest target attainment rate (25.8%) and performed equally for VGCV with the Franck model formula (35.3% for both). CONCLUSION: The ML algorithms exhibit good performances in comparison with previously validated models and should be evaluated prospectively.

Incidence and outcomes of kidney replacement therapy for end-stage kidney disease due to primary glomerular disease in Europe: findings from the ERA Registry.

BACKGROUND: Primary glomerular disease (PGD) is a major cause of end-stage kidney disease (ESKD) leading to kidney replacement therapy (KRT). We aimed to describe incidence (trends) in individuals starting KRT for ESKD due to PGD and to examine their survival and causes of death. METHODS: We used data from the European Renal Association (ERA) Registry on 69 854 patients who started KRT for ESKD due to PGD between 2000 and 2019. ERA primary renal disease codes were used to define six PGD subgroups. We examined age and sex standardized incidence, trend of the incidence and survival. RESULTS: The standardized incidence of KRT for ESKD due to PGD was 16.6 per million population (pmp), ranging from 8.6 pmp in Serbia to 20.0 pmp in France. Immunoglobulin A nephropathy (IgAN) and focal segmental glomerulosclerosis (FSGS) had the highest incidences, of 4.6 pmp and 2.6 pmp, respectively. Histologically non-examined PGDs represented over 50% of cases in Serbia, Bosnia and Herzegovina, and Romania and were also common in Greece, Estonia, Belgium and Sweden. The incidence declined from 18.6 pmp in 2000 to 14.5 pmp in 2013, after which it stabilized. All PGD subgroups had 5-year survival probabilities above 50%, with crescentic glomerulonephritis having the highest risk of death [adjusted hazard ratio 1.8 (95% confidence interval 1.6-1.9)] compared with IgAN. Cardiovascular disease was the most common cause of death (33.9%). CONCLUSION: The incidence of KRT for ESKD due to PGD showed large differences between countries and was highest and increasing for IgAN and FSGS. Lack of kidney biopsy facilities in some countries may have affected accurate assignment of the cause of ESKD. The recognition of the incidence and outcomes of KRT among different PGD subgroups may contribute to a more individualized patient care approach.

Digoxin Pharmacokinetics in Patients with Obesity Before and After a Gastric Bypass or a Strict Diet Compared with Normal Weight Individuals.

BACKGROUND AND OBJECTIVE: Several drugs on the market are substrates for P-glycoprotein (P-gp), an efflux transporter highly expressed in barrier tissues such as the intestine. Body weight, weight loss, and a Roux-en-Y gastric bypass (RYGB) may influence P-gp expression and activity, leading to variability in the drug response. The objective of this study was therefore to investigate digoxin pharmacokinetics as a measure of the P-gp phenotype in patients with obesity before and after weight loss induced by an RYGB or a strict diet and in normal weight individuals. METHODS: This study included patients with severe obesity preparing for an RYGB (n = 40) or diet-induced weight loss (n = 40) and mainly normal weight individuals scheduled for a cholecystectomy (n = 18). Both weight loss groups underwent a 3-week low-energy diet (<1200 kcal/day) followed by an additional 6 weeks of <800 kcal/day induced by an RYGB (performed at week 3) or a very-low-energy diet. Follow-up time was 2 years, with four digoxin pharmacokinetic investigations at weeks 0, 3, and 9, and year 2. Hepatic and jejunal P-gp levels were determined in biopsies obtained from the patients undergoing surgery. RESULTS: The RYGB group and the diet group had a comparable weight loss in the first 9 weeks (13 ± 2.3% and 11 ± 3.6%, respectively). During this period, we observed a minor increase (16%) in the digoxin area under the concentration-time curve from zero to infinity in both groups: RYGB: 2.7 µg h/L [95% confidence interval (CI) 0.67, 4.7], diet: 2.5 µg h/L [95% CI 0.49, 4.4]. In the RYGB group, we also observed that the time to reach maximum concentration decreased after surgery: from 1.0 ± 0.33 hours at week 3 to 0.77 ± 0.08 hours at week 9 (-0.26 hours [95% CI -0.47, -0.05]), corresponding to a 25% reduction. Area under the concentration-time curve from zero to infinity did not change long term (week 0 to year 2) in either the RYGB (1.1 µg h/L [-0.94, 3.2]) or the diet group (0.94 µg h/L [-1.2, 3.0]), despite a considerable difference in weight loss from baseline (RYGB: 30 ± 7%, diet: 3 ± 6%). At baseline, the area under the concentration-time curve from zero to infinity was -5.5 µg h/L [95% CI -8.5, -2.5] (-26%) lower in patients with obesity (RYGB plus diet) than in normal weight individuals scheduled for a cholecystectomy. Further, patients undergoing an RYGB had a 0.05 fmol/µg [95% CI 0.00, 0.10] (29%) higher hepatic P-gp level than the normal weight individuals. CONCLUSIONS: Changes in digoxin pharmacokinetics following weight loss induced by a pre-operative low-energy diet and an RYGB or a strict diet (a low-energy diet plus a very-low-energy diet) were minor and unlikely to be clinically relevant. The lower systemic exposure of digoxin in patients with obesity suggests that these patients may have increased biliary excretion of digoxin possibly owing to a higher expression of P-gp in the liver.

Trabecular Bone Score Improves Early After Successful Kidney Transplantation Irrespective of Antiresorptive Therapy and Changes in Bone Mineral Density.

Background: Trabecular bone score (TBS) is a new tool to assess trabecular bone microarchitecture based on standard dual-energy x-ray absorptiometry (DXA) of lumbar spine images. TBS may be important to assess bone quality and fracture susceptibility in kidney transplant recipients (KTRs). This study aimed to investigate the effect of different bone therapies on TBS in KTRs. Methods: We reanalyzed DXA scans to assess TBS in 121 de novo KTRs at baseline, 10 wk, and 1 y. This cohort, between 2007 and 2009, participated in a randomized, placebo-controlled trial evaluating the effect of ibandronate versus placebo in addition to vitamin D and calcium. Results: Although bone mineral density (BMD) Z scores showed a subtle decrease in the first weeks, TBS Z scores increased from baseline to 10 wk for both treatment groups, followed by a slight decline at 12 mo. When comparing treatment groups and adjusting for baseline TBS, there were no differences found in TBS at 12 mo (P = 0.419). Correlation between TBS and BMD at baseline was weak (Spearman's ρ = 0.234, P = 0.010), and change in TBS was not correlated with changes in lumbar spine BMD in either of the groups (ρ = 0.003, P = 0.973). Conclusions: Treatment with ibandronate or vitamin D and calcium did not affect bone quality as measured by TBS in de novo KTRs, but TBS increased early, irrespective of intervention. Changes in TBS and BMD during the study period were not correlated, indicating that these measurements reflect different aspects of bone integrity. TBS may complement BMD assessment in identifying KTRs with a high fracture risk.

European chronic kidney disease registries for children not on kidney replacement therapy: tools for improving health systems and patient-centred outcomes.

Chronic kidney disease (CKD) in children, from birth to late adolescence, is a unique and highly challenging condition that requires epidemiological research and large-scale, prospective cohort studies. Since its first launch in 2007, the European Society for Paediatric Nephrology/European Renal Association (ESPN/ERA) Registry has collected data on patients on kidney replacement therapy (KRT). However, slowing the progression of CKD is of particular importance and thus the possibility to extend the current registry dataset to include patients in CKD stages 4-5 should be a priority. A survey was sent to the national representatives within the ESPN/ERA Registry to collect information on whether they are running CKD registries. All the representatives from the 38 European countries involved in the ESPN/ERA Registry participated in the survey. Eight existing CKD registries have been identified. General characteristics of the national registry and detailed data on anthropometry, laboratory tests and medications at baseline and at follow-up were collected. Results provided by this survey are highly promising regarding the establishment of an ESPN CKD registry linked to the ESPN/ERA KRT registry and subsequently linking it to the ERA Registry with the same patient identifier, which would allow us to monitor disease progression in childhood and beyond. It is our belief that through such linkages, gaps in patient follow-up will be eliminated and patient-centred outcomes may be improved.

Systemic inflammation early after kidney transplantation is associated with long-term graft loss: a cohort study.

Background: Early graft loss following kidney transplantation is mainly a result of acute rejection or surgical complications, while long-term kidney allograft loss is more complex. We examined the association between systemic inflammation early after kidney transplantation and long-term graft loss, as well as correlations between systemic inflammation scores and inflammatory findings in biopsies 6 weeks and 1 year after kidney transplantation. Methods: We measured 21 inflammatory biomarkers 10 weeks after transplantation in 699 patients who were transplanted between 2009 and 2012 at Oslo University Hospital, Rikshospitalet, Norway. Low-grade inflammation was assessed with predefined inflammation scores based on specific biomarkers: one overall inflammation score and five pathway-specific scores. Surveillance or indication biopsies were performed in all patients 6 weeks after transplantation. The scores were tested in Cox regression models. Results: Median follow-up time was 9.1 years (interquartile range 7.6-10.7 years). During the study period, there were 84 (12.2%) death-censored graft losses. The overall inflammation score was associated with long-term kidney graft loss both when assessed as a continuous variable (hazard ratio 1.03, 95% CI 1.01-1.06, P = 0.005) and as a categorical variable (4th quartile: hazard ratio 3.19, 95% CI 1.43-7.10, P = 0.005). In the pathway-specific analyses, fibrogenesis activity and vascular inflammation stood out. The vascular inflammation score was associated with inflammation in biopsies 6 weeks and 1 year after transplantation, while the fibrinogenesis score was associated with interstitial fibrosis and tubular atrophy. Conclusion: In conclusion, a systemic inflammatory environment early after kidney transplantation was associated with biopsy-confirmed kidney graft pathology and long-term kidney graft loss. The systemic vascular inflammation score correlated with inflammatory findings in biopsies 6 weeks and 1 year after transplantation.

Hybrid and SARS-CoV-2-vaccine immunity in kidney transplant recipients.

BACKGROUND: Kidney transplant recipients (KTR) are at high risk for severe COVID-19 and have demonstrated poor response to vaccination, making it unclear whether successive vaccinations offer immunity and protection. METHODS: We conducted a serologically guided interventional study where KTR patients that failed to seroconvert were revaccinated and also monitored seroconversion of KTR following the Norwegian vaccination program. We analysed IgG anti-RBD Spike responses from dose 2 (n = 432) up to after the 6th (n = 37) mRNA vaccine dose. The frequency and phenotype of Spike-specific T and B cell responses were assessed in the interventional cohort after 3-4 vaccine doses (n = 30). Additionally, we evaluated the Specific T and B cell response to breakthrough infection (n = 32), measured inflammatory cytokines and broadly cross-neutralizing antibodies, and defined the incidence of COVID-19-related hospitalizations and deaths. The Norwegian KTR cohort has a male dominance (2323 males, 1297 females), PBMC were collected from 114 male and 78 female donors. FINDINGS: After vaccine dose 3, most KTR developed Spike-specific T cell responses but had significantly reduced Spike-binding B cells and few memory cells. The B cell response included a cross-reactive subset that could bind Omicron VOC, which expanded after breakthrough infection (BTI) and gave rise to a memory IgG+ B cell response. After BTI, KTR had increased Spike-specific T cells, emergent non-Spike T and B cell responses, and a systemic inflammatory signature. Late seroconversion occurred after doses 5-6, but 38% (14/37) of KTR had no detectable immunity even after multiple vaccine doses. INTERPRETATION: Boosting vaccination can induce Spike-specific immunity that may expand in breakthrough infections highlighting the benefit of vaccination to protect this vulnerable population. FUNDING: CEPI and internal funds.

High number of hypoglycaemic episodes identified by CGM among home-dwelling older people with diabetes: an observational study in Norway.

BACKGROUND: A scoping review from 2021 identified a lack of studies on the incidence, prevention and management of hypoglycaemia in home-dwelling older people with diabetes. The aim of this study was to investigate the frequency and duration of hypoglycaemic episodes measured by continuous glucose monitoring (CGM) in older people with diabetes who received home care and who were treated with glucose-lowering medications, and to compare the frequency and duration of hypoglycaemic episodes between subgroups of the study population according to demographic and clinical variables. METHODS: This was an observational study investigating the occurrence of hypoglycaemia in people with diabetes aged ≥ 65 years. Data were collected using blinded continuous glucose monitoring (CGM, iPro2) for 5 consecutive days. Frequency and duration of hypoglycaemic episodes were assessed using a sensor glucose cut-off value of 3.9 mmol/L. A blood sample for measurement of HbA1c and creatinine-based eGFR (CKD-EPI) was obtained during the monitoring period. Demographic and clinical data were collected from electronic patient records. RESULTS: Fifty-six individuals were enrolled (median age 82 years and 52% were men). Of the 36 participants who were treated with insulin, 33% had at least one hypoglycaemic episode during the five-day period. Among 18 participants who neither used insulin nor sulfonylurea, but other glucose-lowering medications, 44% had at least one hypoglycaemicepisode. Of those with hypoglycaemic episodes, 86% lived alone. The median duration of the hypoglycaemia was 1 h and 25 min, ranging from 15 min to 8 h and 50 min. CONCLUSION: This study identified an unacceptably high number of unknown hypoglycaemic episodes among older home-dwelling people with diabetes receiving home care, even among those not using insulin or sulfonylurea. The study provides essential knowledge that can serve as a foundation to improve the treatment and care for this vulnerable patient group. The routines for glucose monitoring and other prevention tasks need to be considered more comprehensively, also, among those treated with glucose-lowering medications other than insulin.

Proteome deconvolution of liver biopsies reveals hepatic cell composition as an important marker of fibrosis.

Human liver tissue is composed of heterogeneous mixtures of different cell types and their cellular stoichiometry can provide information on hepatic physiology and disease progression. Deconvolution algorithms for the identification of cell types and their proportions have recently been developed for transcriptomic data. However, no method for the deconvolution of bulk proteomics data has been presented to date. Here, we show that proteomes, which usually contain less data than transcriptomes, can provide useful information for cell type deconvolution using different algorithms. We demonstrate that proteomes from defined mixtures of cell lines, isolated primary liver cells, and human liver biopsies can be deconvoluted with high accuracy. In contrast to transcriptome-based deconvolution, liver tissue proteomes also provided information about extracellular compartments. Using deconvolution of proteomics data from liver biopsies of 56 patients undergoing Roux-en-Y gastric bypass surgery we show that proportions of immune and stellate cells correlate with inflammatory markers and altered composition of extracellular matrix proteins characteristic of early-stage fibrosis. Our results thus demonstrate that proteome deconvolution can be used as a molecular microscope for investigations of the composition of cell types, extracellular compartments, and for exploring cell-type specific pathological events. We anticipate that these findings will allow the refinement of retrospective analyses of the growing number of proteome datasets from various liver disease states and pave the way for AI-supported clinical and preclinical diagnostics.